1296721 has 2 divisors, whose sum is σ = 1296722. Its totient is φ = 1296720.

The previous prime is 1296703. The next prime is 1296727. The reversal of 1296721 is 1276921.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1166400 + 130321 = 1080^2 + 361^2 .

It is a cyclic number.

It is not a de Polignac number, because 1296721 - 2⁵ = 1296689 is a prime.

It is a Chen prime.

It is an alternating number because its digits alternate between odd and even.

It is a self number, because there is not a number n which added to its sum of digits gives 1296721.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1296727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 648360 + 648361.

It is an arithmetic number, because the mean of its divisors is an integer number (648361).

2^1296721 is an apocalyptic number.

It is an amenable number.

1296721 is a deficient number, since it is larger than the sum of its proper divisors (1).

1296721 is an equidigital number, since it uses as much as digits as its factorization.

1296721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1512, while the sum is 28.

The square root of 1296721 is about 1138.7365806015. The cubic root of 1296721 is about 109.0474500926.

The spelling of 1296721 in words is "one million, two hundred ninety-six thousand, seven hundred twenty-one".